Bleaching compositions have been extensively described in laundry applications as laundry detergents, laundry additives or even laundry pretreaters.
Indeed, it is known to use such bleach-containing compositions in laundry pretreatment applications to boost the removal of encrusted stains/soils and "problem" stains, such as grease, coffee, tea, grass, mud/clay-containing soils, which are otherwise particularly difficult to remove by typical machine washing. However, a drawback associated with such bleach-containing compositions is that said compositions may damage fabrics, resulting in dye damage and/or loss of tensile strength of the fabric fibers, especially when used in pretreatment applications under stressed conditions, e.g. when applied directly onto the fabric and left to act onto said fabric for prolonged periods of time before washing said fabrics, especially when the fabric to be treated is contains metal ions such as copper, iron, manganese, or chromium. Without being limited by theory, it is believed that peroxygen bleach can be responsible for the dye and fabric damage associated with these bleaching compositions. It is furthered believed that these metal ions on the surface of the fabrics, especially on cellulosic fabrics, catalyze the decomposition of peroxygen bleaches like hydrogen peroxide. Thus, the decomposition of the peroxygen bleach can result in fabric and/or dye damage.
When said compositions are applied directly to fabrics, the different components in said compositions diffuse or migrate, possibly at different rates, through the fabric fibers. This is also true for the peroxygen bleach component of bleaching compositions designed for the pretreatment of fabrics.
Now a solution to the damage resulting from pretreating fabrics with bleaching compositions comprising peroxygen bleach is provided by adding a certain fabric protection agent which acts to reduce fabric and/or dye damage. This fabric protection agent, aminotri(methylene phosphonic acid)--hereinafter ATMP--has been found to considerably reduce the damage associated with the treatment of fabrics with peroxygen bleach-containing compositions, especially those fabrics which are contaminated with metal ions.
Accordingly, the present invention solves the long-standing need for an effective, bleaching composition suitable for use as a pretreater which does not promote damage to fabrics. Moreover, the compositions of the present invention provide excellent performance when used in other applications apart from laundry pretreater application, such as in other laundry applications, as a laundry detergent or laundry additive, or even in hard surface cleaning applications or in carpet cleaning applications.
In the preferred compositions of the invention, which are liquid compositions, ATMP further provides the benefit of exceptional chemical stability for the peroxygen bleach.